This application claims the priority of German patent document 199 37 765, filed Aug. 10, 1999 the disclosure of which is expressly incorporated by reference herein.
The invention relates to a device for the accurate positioning of an antenna of a satellite. In technical terms, this is known as an xe2x80x9cantenna pointing mechanismxe2x80x9d, or xe2x80x9cAPMxe2x80x9d for short.
Placing the antenna on or at a universal joint (gimbal) and providing a drive for each of the axles extending perpendicular with respect to one another is common knowledge. This drive may be an angular resolver, e.g., a stepper motor or a toothed gearing.
The following are objects of the invention:
during the start phase, the antenna and universal joint should not exert any force on the drive;
during the start phase, the antenna and the universal joint should be in a locked position;
at the end of the start phase, the antenna should accurately take a preset position; and
during the operation, it should be possible to change the position of the antenna in a highly precise manner.
These objects are achieved according to the invention by providing a gear for accurate positioning of an antenna of a satellite in space, in which the antenna is fastened to a plate mounted on gimbals, with said plate capable of being swivelled around two axles running perpendicular with respect to one another and stored in bearings, and with a rotary drive provided for each axle, characterized in that the rotary drive includes an arm of a lever, said arm being connected to the axle, and a linear drive that freely affects the arm.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.